US2313918A - Controlling mechanism for ironing machines - Google Patents

Description

Marcif 16,1943; H. H. BROWNLEE I 2,313,918

CONTROLLING I cmIsfl FOR moans pmcamns Filed Dec. 13, 1958 2 Sheets-Sheet 1 INVENTOR HHERBE/PZSO/V BROW/VLEE.

ATTORNEY MarcHlG, 1943. H. H. BROWNLEE CONTROLLING MECHANISM FOR IRONING MACHINES Filed Dec. 13, 1938 2 Sheets-Sheet 2 50 J/ INVENTOR J HERBERT-50A BROWN-LEE ATTORNEY Patented Mar. 16, 1943 7 UNITED STATES PATENT OFFICE CONTROLLING FOR IROlVIFG Henry Herbertson Brownlee, New York, N. Y. Application December 13,1938, Serial No. 245,391

8 Claims.

This invention relates to the control of ironing machines and is especially applicable to power actuated garment IPIGSSBS. Its objects are simplicity of control and speed of operation of'the machines, accuracy in determining pressing periods and uniformity of results. This application is a continuation-in-part of application Serial No. 187,593 filed January 29, 1938, .by the same inventor.

In the laundry and tailoring business numerous types of machines are used for the purpose of ironing and pressing garments after the washing or dry cleaning operations. A common machine ior this step is operated by pneumatic force applied to a heated ironing head to bring it down and hold it under pressure against a garment that the machine attendant had adin the padding of the the controlling current a mesh screen assemble buck serves as the other,

the garment being effected by the change in resistance of the moist garment as it reaches its' required dry state. In another arrangement,

the power disablement is efiected by a change in current through the justed upon a padded, and sometimes also heated, buck. To work such a machine it is necessary for the attendant to exercise control of compressed air for the energization. of the pneumatic device. Hand operated air valves have been used for this purpose and, to protect the attendant from accidentally operating the press with one hand while adjusting the garment on the buck with the other, a dual valve control system requiring the joint use of two hands to close the press has been-resorted to. Under that system the attendant must keep both hands on the controls until the head has been locked in the ironing position and thereafter must operate a release valve to open the press.

In the use of a garment press equipped according to this invention, all guess work regarding drying is eliminated. The head will not stay down too long thereby retarding production and. in many instances, over cooking the garments. Nor will the head rise too soon. Nor will the operator be required to open the press one or more times to inspect the garment and, upon finding it still wet, be obliged to close it again,

thereby also retarding production. Instead a device under the control of the garment itself, operating after the initial closing 01' the press, determines the pressing time. The operation is such that the power is automatically disabled thereby releasing the pressing head at the proper time, this being when the garment has reached the desired state of dryness. Such a device may be one that is sensitive to the flow of electric current through the garment. Either the buck or the head may have associated with it an electemperature, a thermostat being associated with either head or buck for this purpose.

In the drawings, Fig. 1 is a side elevation of a garment pressing machine; Fig. 2, a vertical cross section of a magnetic air valve; Fig. 3, a

diagrammatic representation of a system of controlling circutis; Fig. 4, a plan view in outline of an ironing head showing insulated electrodes for contacting with and completing a path for garments; Fig. 5,, an end view of an alternative ironing head, partly in section; equipped with a thermostat device; Fig.

6, a diagram of a controlling circuit for the thermostat; and Fig. 7, plan view of a buck with section of the padding removed to show a mesh screen adapted for use as an electrode.

A press base or frame I supports a table-like top 2, on which is mounted a goose neck support 3 for a lower or padded buck 4. An upwardly extending bracket 5 supports a rocker arms 6, which carries at its forward end an upper or ironing head T. arm carriesa counterweight 8 and is connected to the piston 9 of a pneumatic cylinder III by a system of levers working on the toggle .principle. The heating of the head is commonly provided 'i'or'lby a system of steam pipes, and channels within the head, not shown. The movable parts are shown by full lines in the closed position of the press and by dotted lines in the open or normal position.

. A magnetic air valve II is mounted alongside the pneumatic device and serves when energized to open the cylinder above the piston to a compressed air source through a duct l2. When the. air is thus let in the piston descends pushing down on one arm of a bell crank lever l3, and, at the end 01 its stroke, bringing the other arm almost into alignment with the link H,

' therebygreatly adding to the force exerted on tractile springs trode, or a pair of electrodes. for bringing the garment into the controlling circuit. In one construction the head serves as one electrode and the garment.

8 open the press. The valve provides for a short passage for the compressed air through the duct Mo to the cylinder in and, therefore, for quick action both in closing and opening the press. This valve has two plugs, better shown in Fig. 2, one, l1, normally closing the inlet II to the A rearward extension of this On the release of the air the re- I5, l6 aided by the counterweight outlet l9 leading to the cylinder. The other 23, is normally in open position to an exhaust outlet 2!. The plugs are Joined by a spacer pin 22.

A magnet 23 when energized by electric current in its coil 24 attracts the armature 25 which depresses a plunger 26 against a spring 21 which with two normally open manual switches 354i,

and a source of alternating current 32. This source also supplies current at the proper voltages for the heaterafilaments, plates and grids of two tubes, one a bufier tube 33 and the other an output or power tube 3. For the purposes of such current distribution a voltage divider resistor 35 is used. Taps from this resistor lead to the various elements of the tubes and'their associated circuit connections. In one path current flows through the resistor 35 and the heater 36 of tube 34. In another, current flows through the plate 31 of tube 33, resistor 33, condenser 39, these two latter elements being in parallel, and through the heater 35. A third path is that through the plate of tube 34, the coil of relay 40 relay 40. This relay then attracts its armature and opens the circuit through the air valve II. The press opens and the cycle is completed for one ironing operation. Adjustment of the resistance of the circuit through the garment in order to predetermine the drying time may be obtained by means of rheostat 42 and condenser 43.

and a filter condenser 4!, the latter two elements being in parallel. The path for the control currentthrough the garment includes a rheostat 42, protective resistance 43, the head 1 of the press, a garment 44 therein, a fine mesh screen 45, associated with the padding of the buck 4 a second protective resistance 41 and condenser 48.

The operation of the circuit is as follows: Prior to the closing of the press and therefore of the circuit through the garment, current through the plate of tube 33 is at a minimum. Under this condition there is bias on the controlling grid 49, and a minimum voltage drop in resistor 38. Grid 50 is sufficiently positive to permit effective current flow through the plate circuit of tube 34 to energize relay 40. There is at such times a maximum current in this last mentioned circuit. When, however, the press is in operation and current is flowing through the garment, positive potential is applied to the grid 45 of tube 33 thus permitting plate current flow through that tube. This, in turn, causes 9. voltage to be developed across resistor 38 and grid 50 of tube 34 to be biased thus preventing sufficient current to flow through the plate of tube 34 to maintain relay energized.

The foregoing sequence of operations occurs before and after the attendant has applied power to the press and this he does by closing the two switches 3|l-3l, one with each hand. Current thereupon flows through the coil of air valve ii and causes the head 1 to descend upon the garment. After the head descends, the circuit previously mentioned through relay 43 is deenergized. Relay 4!! by releasing its armature closes its contact and maintains the air valve energized. The head of the press continues its pressing action on the garment until the latter reaches the proper dry state, whereupon the resistance of the garment increases to a point where the bias on the grid is sufllciently increased and the bias on the grid is sufliciently decreased to permit flow of current through tube 34 and Instead of using the head for one electrode and the screen inthe buck for the other, two electrodes SI, 52, or several pair of such electrodes, as shown in Fig. 4, may be embedded in the head, being set flush with the face of the head in an insulating block 53. The controlling circuit for this construction would be the same as that shown in Fig. 3, except that electrodes 5| and 52 would take the place of the head I and mesh screen 45.

In case the drying time is to be determined by temperature changes in the head or buck, a thermostat having opposing contacts 54, 55, shown in Fig. 5 as inserted just inside the ironing surface of the head I, would be arranged to close the circuit directly to the valve II when the head is cooled by contact with a damp garment and to open that circuit when it reaches its normal temperature, at which time the garment will have reached its proper dry condition.

A suitable controlling circuit using such a thermostat is shown in Fig. 6. Upon the joint closing of switches 30a, am, relay 40a is brought in circuit with the valve H. Then when the head is down and is cooled by the damp garment the thermostat contacts 54, 55 close and provide through the then closed contacts of relay 43 a substitute path to maintain the valve energized and the head down. The subsequent opening of the thermostat contacts, when the temperature of the head is restored, releases the relay. By this arrangement the relay contacts remain open until the, attendant again actuates the control.

switches 30a, 3 la for a. subsequent pressing operation.

The mesh screen, as shown in Fig. 7, would be of such fineness that, when placed directly beneath the top covering of the pad on the buck, it would not leave its mark on the garment. Preferably it would have the general shape of and fully cover the entire ironing area of the buck. It should be made of non-corrosive wire.

I claim:

1. A textile press comprising a stationary buck member, a pivoted head member, fluid motor power means for actuating said head, a valve for controlling said head member, an electrode insulatedly mounted on one of said members, the other of said members being electrically conductive, manually operated means to actuate said valve to move said head member toward the buck member, a balanced electric circuit having two conditions of balance, and means responsive to the variation of resistance between said electrode and said conductive member to cause said circuit to change from one position of balance to the other to actuate said valve to move said head member away from the buck member.

2. A textile press for moist articles comprising a buck member, a pivoted head member, means for actuating said head member into engagement with and away from the buck member including motor means, valve means for controlling said motor means, a pair of electrodes spaced from each other at least when the head member is closed upon an article to pass current therebetween utilizing the moisture of the article, manually operated means to actuate said valve means to move said head member toward the buck member, a balanced electric circuit having two condi tions of balance and connected with the electrodes, and means responsive to the variation of resistance between said electrodes to cause said circuit to change from one condition of balance to the other to actuate said valve means to move said head member away from the buck member.

3. A pressing machine for a moist article comprising a pair of cooperating members at least one of which is mounted for relative movement into and out of engagement with the other, power operated means to move at least one of said cooperating members, manual means controlling the power operated means to bring the cooperating members into engagement and hold them in engagement, a pair of electrodes in close proximity to each other at least when said cooperating members are in engagement with each other and utilizing the moisture in the article between the cooperating members to conduct current therebetween when a potential is applied to the electrodes, and an electric circuit responsive to variations of resistance between said electrodes to control said power operated means and separate the cooperating members.

4. A machine for performing an operation on a moist article comprising aheated member, means to move said member into contact with said article, the temperature of said member being sufficient to produce steam in the vicinity of said article, a pair of electrodes in the vicinity of said article, means to utilize the steam produced by heating said article to vary the resistance path between said electrodes, means to apply a potential across said electrodes, and means to utilize the variation of current between said electrodes to cause said member to move out of contact with said article.

5. A machine for performing an operation on an article, comprising a pair of electrodes positioned one on each side of saidarticle, a porous cover member positioned between one of said electrodes and said article, means to rapidly vary the moisture content of said article, whereby some moisture is driven into said porous cover mem-- ber, means to apply a potential between said electrodes, whereby current is caused to flow therebetween which is proportional to the moisture contained in said article and in said porous cover member, and means to stop the operation of said first mentioned means-When said current has varied to a predetermined value.

6. A textile press comprising a pair of cooperating pressing members for pressing work positioned between them, power operated means to cause relative movement of said members into and out of engagement with each other, a pair of electrodes positioned adjacent the work being pressed, means to cause a current to flow between said electrodes when said press is operated which is proportional to the amount of humidity in said work, means to cause variation of said current to control said power operated means, and means to adjust said third mentioned means to cause it to respond to different predetermined variations of current.

7. A power operatedgarment press having a stationary part and a movable ironing part,electrical r mechanism for determining the period of application of power to said press, an electrode associated with said stationary part, and a circuit including said electrode and said movable part and adapted to carry current through a garment in the press for controlling said mechanism.

8. A textile press comprising two pressing members, one of which is movable towards and away from the other, fluid power motor means to actuate said movable member, a valve for controlling said motor means, an electrode insulatedly mounted on one of said members, a second electrode cooperatively associated with said first mentioned electrode, said electrodes forming parts of an electric conductive path subject to resistance variations upon the closing of the press on a wet fabric, manually controlled means to actuate said valve to close the press, and electrical apparatus operatively associated with said conductive path and responsive to a predetermined variation of resistance between said electrodes to actuate said valve to open the press.

H. HERBERTSON BROW'NLEE.

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